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Measurement of Total Calcium in Neurons by Electron Probe X-ray Microanalysis
Published on: November 20, 2013
Electron probe X-ray microanalysis for the study of cell physiology.
E Fernandez-Segura1, Alice Warley
1Department of Histology, Faculty of Medicine, University of Granada, E-10871, Granada, Spain.
Methods in Cell Biology
|July 12, 2008
Summary
Electron probe X-ray microanalysis (EPXMA) is a powerful tool for analyzing elemental composition in biological specimens. This technique identifies, localizes, and quantifies elements in whole cells and intracellular compartments.
Area of Science:
- Analytical Electron Microscopy
- Cellular Biology
- Biophysics
Background:
- Electron probe X-ray microanalysis (EPXMA) is a key technique in analytical electron microscopy for biological studies.
- It enables elemental identification, localization, and quantification at both cellular and subcellular levels.
Purpose of the Study:
- To outline the principles of X-ray emission in EPXMA.
- To provide methods for specimen preparation for whole cells and cryosectioned cells.
- To detail quantitative analysis of spectra and highlight potential challenges.
Main Methods:
- Utilizing Scanning Electron Microscopy (SEM) or Transmission Electron Microscopy (TEM) for whole cell analysis.
- Analyzing thin sections of cryoprepared cells for intracellular compartment analysis.
- Applying EPXMA for elemental identification, localization, and quantification.
Main Results:
- EPXMA allows rapid assessment of ion transport changes in stimulated whole cells.
- Detailed ionic content of intracellular compartments (mitochondria, ER, lysosomes) can be obtained from cryosections.
- Quantitative data derived from spectra provides precise elemental information.
Conclusions:
- EPXMA is a versatile technique for investigating cell physiology.
- It offers insights into elemental distribution and dynamics within biological systems.
- The chapter provides a comprehensive guide to EPXMA application in cell biology research.
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